Ramming device for firearms



Se t. 5, 1961 c. M. CHRISTIANSSON 2,998,756

RAMMING DEVICE FOR FIREARMS Filed Dec. 11, 1958 FIG.

FIG. 3

INVENTOR.

CARL- MAUE/TZ CHE/STM/VSSO/V ATTOEA/EYS 2,998,756 RAMMING DEVICE FOR FIREARMS Carl Mauritz Christiansson, Bofors, Sweden, assignor to Aktieholaget B'ofors,'Bofors, Sweden, a corporation of Sweden Filed Dec. '11, 1958, 'Ser. No. 779,641 Claims priority, application-Sweden Dec. '14, 1957 4 Claims. (Cl. 89-47) This invention relates to firearms and, more particularly, to a ramming device for automatic firearms.

Many types of ramming devices are provided with a ramming lug that is actuated by a spring forcewhich executes the ramming movement of the lug and which is intended to be cocked by the recoiling parts ofthe firearm. Since the length of movement of the recoiling parts varies, it is necessary to design the ramming device in such a way that the cocking of the ramming lug is always completed, even at the recoil length. It is also important that the recoiling parts execute their maximum movements without damaging any parts of the ramming assembly. Proper design and cooperation between associated parts are even of greater importance in automatic weapons of large calibers that are designed for a high rate of fire.

Accordingly, it is an object of the present invention to provide a ramming device inwhich the masses to 'be accelerated are as small as possible and in which impact stresses are minimized. 2

Another object of the present invention is to provide a ramming device for automatic firearms in which the movement of the ramming lug is cushioned in, both the ramming and cocking directions so as to impart minimum shocks to the operating parts.

An additional object of the present invention is to;

provide a cocking assembly for automatic firearms in which the length of travel of the ramming lug toward the ramming position is automatically adjusted in response to changes in the firing elevation of the firearm soas to provide for theaddit'ional amount of-ener-gy-that is re-' quired to move a round from a ramming position to a chamber position at increased firing elevations.

Still a further object of the present invention is to provide a ramming assembly for recoiling type automatic; firearms which will automatically relieve the cocking parts of the ramming lug from the continued application. of

force by the recoiling parts of the firearm as soonas the ramming lug has been moved into the cocked position.

All of the foregoing and still further objects and advantages of this invention 'will become apparent from a study of the following specification, taken in connection with the accompanying drawing, wherein:

FIGURE 1 is a fragmentary perspective view of an automatic firearm embodying a ramming device made in accordance with the present invention;

FIGURE 2 is a transverse cross-section taken along line 22 of FIGURE 1 showing the cross-bar forming a part of the present invention in an initial position;

FIGURE 3 is similar to FIGURE 2, showing the crossbar in a cocking position; and

FIGURE 4 is a side view of a firearm embodying a cocking mechanism made in accordance with the present invention in several elevated .positions.

Referring now more in detail to the drawing, and more particularly to FIGURES 1 to 3 thereof, a cocking mechanism made in accordance wth the present invention is shown in operative association within an automatic type firearm. This mechanism includes a frame 1 that is fixed to the elevating non-recoiling parts of the firearm, and is provided with a pair of elongated slots 2 which support a cross-bar 3 for reciprocating longitudinal move- United States a Patent ment therewithin. The center rearwardly facing portion of the cross-bar 3 has a buffer device 4 of any desired type that serves as a cushion when engaged by the ramming lug 12 which will be hereinafter more fully described.

The ends 3a of the cross-bar 3 extend outwardly through the slots 2 and are provided with obliquely formed bearing surfaces, 5, facing in opposite directions, that are intended to coact with mating surfaces 6 on actuated bars 7 that are fixed to recoiling parts of the elevating mass that includes the barrel and breech easing of the firearm. A pair of rods 8, having head 9 at one end'and piVotally connected to actuating levers 10 by means of pins 10a at the opposite end extend alongside and parallel to the frame 1. These rods are slidably received within bearing portions 8a at the opposite outer ends of the cross-bar 3 so that the heads 9 of the rods 8 serve as limit stops which limit the forward movement of the crossbar 3 toward the initial position, thus further limit ing the forward movement ofthe ramming lug 12. The

- ramming lug 12 is slidably' supported within inwardly opening grooves 13 in the opposite sides of the main frame 1 for reciprocating longitudinal movement between an initial cocked position illustrated in FIGURE 1, and an actuated ramming position in abutment with the bufier device 4 of the cross-bar 3. In the initial position, the ramming lug 12 is releasably locked in the retracted cocked .position against the action of a spring force source 12a by a suitable latch mechanism that may be automatically controlled by associated parts of the firearm. v

As soon as the ramming ing is released, it'moves forwardly under the action of the spring force source 12a to drive the next round into the firing chamber of the. firearm, the forward ramming movement of the lug 12 being limited by the position of the buifer device 4 car-; ried by the cross-bar 3. When the round is fired by the firearm, the recoiling bars 7 move rearwardly into driving engagement with the outer ends 3a of the crossbar 3 and move the cross-bar 3 rearwardly against the action of the compression coil springs 14. Such rearward move- As the cross-bar 3 approaches the rearmost part of its.

stroke, the oblique surfaces 6 of the recoiling bars 7 direct the opposite ends 3;: of the cross-bar 3 into oppositely directed oblique terminal portions'15, 16 of the slots 2,' whereby continued rearward movement of the recoiling bars 7 bypasses the ends 3a of the cross-bar, as shown in phantom lines in FIGURE 1, and in FIGURE 3. During the last part of the recoil movement as well as during the first part of the runout movement of the bars 7 and the rods 8, the cross-bar 3 is held in the position shown in phantom lines in FIGURE 1, the cross-bar then being pressed againstthe oblique terminal portions 15 and 16 under the influence of the spring force source 12a of the ramming lug. Also the springs 14 strive to move the cross bar 3 towards the said oblique terminal portions 15 and 16. Due to the obliquity of these portions, the said spring forcesalso strive to turn the crossbar 3 towards the bars 7. When the oblique surfaces 6 of the bars 7 pass the oblique surfaces 5 on the ends 3a of thecross-bar 3 during the runout movement, because of the turning of the cross-bar 3 the oblique surfaces 5- will immediately follow the obliqu'e surfaces '6, without;

3 upon the parts are ready for the next round to be fired.

It will be noted that during both the recoil movements and the return or runout movements of the cross-bar, there will not be any impact stresses set up in the ramming device. The movement of the cross-bar 3 toward the initial position is limited by the heads or stops 9 of the rods 8 which thus also limit the ramming movement of the ramming lug 12.

It will be recognized that different amounts of-energy are required to move a round from the ramming position to the chamber position depending upon the firing elevation of the firing arm. In order to provide for the additional energy required to move the round from the ramming position to the chamber position in higher firing elevations of the firearm, and to reduce the amount of energy available for ramming the round into the chamber at lower firing elevations, cam means are provided in accordance with the present invention which serve to adjust the ramming stroke of the ramming lug 12. As is more clearly shown in FIGURE 4 of the drawing, the levers 10 to which the rear ends of the rods 8 are pivota'lly connected are secured to one or more rock shafts 11 that are rotatably carried by the main frame of the firearm which may be rotatably supported by bearings upon a stationary mount 19 for movement between selected fin'ng angles. A follower 23 eccentrically carried by each such rock shaft 11 is in sliding or rolling engagement with an arcuate cam or guide rail 20 that has a center of curvature 21 which is eccentric with the pivot axis 18 of the main frame of the firearm. Because of the difference in the positions of the pivot axis 18 and the curvature center 21 of the cam plate 20, the follower 23 secured to the outer end of the lever 22 of each such rock shaft 11 automatically adjusts the position of the rods 8 relative to the main frame or breech casing 17 of the firearm. The movement of the rods 8 is such that as the firing angle of the firearm is increased, the stops or heads 9 are moved forwardly to increase the length of stroke of the ramming lug 12, and as the firing angle of the firing arm is decreased, the limit stops 9 of the rods 8 are moved relatively rearwardly so as to decrease the forward ramming stroke of the ramming lug 12.

The entire mechanism shown in FIGURE 1 is arranged within the firearm. Only the shaft 11 extends outside the breech casing, as shown in FIGURE 4, with the arms 22 and follower 23 disposed on the exterior of the casing.

While this invention has been described with particular reference to the construction shown in the drawing, it is to be understood that such is not to be construed as imparting limitations upon the invention, which is best defined by the claims appended hereto.

Having thus described my invention, I claim as new and desire to secure by Letters Patent:

1. In a recoiling automatic firearm pivotally supported upon a mounting for adjusting firing elevation thereof, said firearm having a main frame slidably supporting a ramming lug for retractable ramming movement in one direction by a spring force source acting between said lug and said main frame, a cross-bar slidably supported for reciprocating longitudinal movement upon said frame for moving said ramming lug in an opposite direction into a cocked position, abutment means carried by said cross-bar for driven movement by recoiling parts of the firearm in said opposite direction from an initial position, guide means carried by said frame effecting partial rotation of said cross-bar out of the path of movement of the recoiling parts of the firearm upon complete retraction of said ramming lug into said cocked position, limit stops carried by said frame in the path of return movement of '4 said cross-bar in said one direction limiting the return movement of said cross-bar relative-te-said cocked position of said ramming lug, a buifer device carried by said cross-bar for impact by said ramming lug during said ramming movement in said one direction, and cam means acting between said main frame and saidmouuting for adjusting the position of saidlimit stop 'i xi'res'ponse to n adjustment of the a ing elevation of said fitam up n said mounting, said cam means adjusting the length of travel of said ramming-lugtowardsaid limit stops in direct proportion-to changesinthe firingelevation ofsaid firearm. V 4

2. In a recoiling automatic firearm as set forth in claim 1, wherein said limit stops comprise a pair of rods each having heads at one end adjacent to the released position of said lug, the opposite ends of said pair of rods being pivotaily supported upon said 'frame adjacent to the cocked position of said lug,-the opposite endear said cross-barbeing slidablysupported upon said rods, and a compression coil spring encircling each of said rods yieldably urging said cross-bar in a direction toward said heads of said rods to return said cross-bar to said initial position. i A t 3. In a recoiling automatic'firearm asset forth in claim 2, further comprising arock shaft pivotally'supported upon said man frame, a-pair of'ievers-each secured at one end upon said rock shaft and pivotally seeured'at the opposite end ofsaid opposite end of each said red, a stationary cam carried by said main frame, and a follower eecentricailysecured upon said rock shaft acting against said cam during-changes in said firing ele vation of said firearm. i i 1 l 4. In a ramming device for a recoiling'automatic the arm having a main frame, a ramming lug slidably supported upon said mainframe for retractable rammingmovement in one direction, a spring forcesourceacting between said ramminglug andsaid main frame yield.-

ably urging said ramming lug in said one :directionand tion from an initial position by the recoiling movement of the recoilingparts of the firearm, guide means :carried by said frame eitectingpartial rotation of said cross bar out of the path of movementofthe recoiling parts ofi the firearm upon complete. retraction :of said. ramming lug into said cocked'position, said guide means including a pair of longitudinal slots in said main frame slidablyreceiviflg' the opposite ends of said cross bar therethrough, each of said slots being a terminalportion adjacent; to said cocked, position of said ramming lug 'angularly relatedto the line of movement of said cross bar, said terminal portions of both of said slots extending'inoppositel d rections to a commodate limited turning movement of said cross bar out of the path of movement of said recoiling parts of the fuearm. Y

References Cited in the file of this patent UN TED ST TES ATENTS:-

1,2 1-7,959 Klaput- Mar. 6, 19.11 2,564,360 Hammar=et al'. Aug. 14, .1951 2,660,928

Marlow Dec; 1,1953 

